Ultrasound-guided ablation for T1N0M0 papillary thyroid carcinoma adjacent and non-adjacent danger triangle area: a retrospective comparative study

Objectives: To compare the safety and efficacy of ultrasound-guided radiofrequency ablation (RFA) in the treatment of T1N0M0 papillary thyroid carcinoma (PTC) with adjacent and non-adjacent danger triangle area (DTA). Materials and methods: This retrospective study involved collecting clinical data of all T1N0M0 PTC patients who underwent RFA between January 2018 and December 2020 at the hospital. A total of 211 patients were enrolled in the study (mean age 43.25 +/- 12.30 years, male-to-female ratio = 1:3). Among them, 91 had adjacent DTA involvement, while 120 had non-adjacent DTA involvement. Comparisons were made between the two groups patients regarding tumor volume changes, technical success rates, tumor disappearance, disease progression, complications. Results: In both groups, the technical success rate was 100%, with a median follow-up period of 30 months. The rates of complete tumor disappearance were 78% (71/91) and 74.2% (89/120) for the adjacent and non-adjacent DTA(p = .517). Disease progression rates were 2.2% (2/91) and 1.7% (2/120) (p > .99), Complication rates were 3.3%(3/91) in the adjacent DTA group and 1.7% (2/120) in the non-adjacent DTA group (p = .654). At 6th month after ablation, the volume reduction rate (VRR) in the non-adjacent DTA group (42.3%) was higher than in the adjacent DTA group (37.3%) (p = .002). However, no significant differences were observed in VRR between the two groups at 1, 3, 12, 18, 24, 30, and 36 months (p > .05). Conclusion: In the treatment of T1N0M0 PTC, the complication rates and short-term efficacy of RFA in adjacent to the DTA did not differ from those of non-adjacent DTA.